Swansea:Liverpool manager Jurgen Klopp said he was infuriated by his team's first-half performance after they came from behind to win 2-1 at Swansea City.

The German lost both England midfielder Adam Lallana and Serbia defender Dejan Lovren to injury during Saturday's game, ruling both players out of international duty.

But it was his side's sloppiness that concerned him most of all, despite a win that saw Liverpool close to within two points of Premier League pace-setters Manchester City.

Liverpool manager Juergen Klopp celebrates after the game. Reuters

"I was very angry," Klopp told reporters at his post-match press conference. "I am 49 years old and I have lost a lot of games and unfortunately will lose a lot more, but today made no sense.

"It was not a day when we should have lost because we could have done so much better in the first half.

"We were all angry at half-time, but at ourselves, so I told them we had to show we are better and show why we were here.

"It looked like we were here to be in a football game, but I wanted them to show we are here because we want to win a football game."

Liverpool were left facing a shock defeat when Leroy Fer capitalised on weak defending to put struggling Swansea ahead in the eighth minute.

But Roberto Firmino equalised in the 54th minute before winning the penalty that James Milner converted to secure all three points at the Liberty Stadium.

"It was a bad start," Klopp said. "We were not ready for this game and it is my responsibility to make sure we are ready.

"Swansea did well, but we were really too static. There was no movement. We knew what they were going to do in training, which would be similar to what they did against (Manchester) City, but it was difficult.

"We were never compact enough for counter-pressing situations. After the goal it didn't immediately become better, but it did eventually."

Guidolin 'worried' Klopp went on to extol the virtues of what former American tennis player Brad Gilbert would term "winning ugly".

"It is always very important that even when it is not a brilliant performance, you are still able to win," he said.

"I have enough fingers to count the brilliant games in the season. That's how it is. Ten is a big number and we've already had a few. That's why the reaction in the second half was so important.

"I didn't think this would be a game where we would be that bad because there was no sign in training that we should be this bad. That shows we are still learning."

Klopp said Lallana and Lovren would miss their respective countries' forthcoming World Cup qualifiers with groin injuries.

"At this moment they have no chance for their national teams," he said.

"Hopefully I have 15 or 16 days to get them back on the pitch again for the next game. It was wet here, but there was no sign that things like this might happen during the middle of the week. It is not too nice."

Swansea manager Francesco Guidolin refused to be drawn on media speculation that he is set to be replaced by either Ryan Giggs or former United States coach Bob Bradley.

"I am not worried about my future, but I am worried about our position in the table," said the Italian, whose side are one place above the relegation zone. "That is all that concerns me.

"I am very disappointed for the team. We have played against very strong teams in this period, but I am confident because I saw my team play for 95 minutes with character and also with quality in the first half.

"If we play this way, I think we can turn our situation around soon. My team is a good team. I am sure we have the qualities to have a good future."